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1.
P. G. Niarchos 《Astrophysics and Space Science》2005,296(1-4):359-370
A new method for the determination of the proximity effects and gravity darkening exponents in contact binaries of W UMa type
is presented. The method is based on Kopal’s method of Fourier analysis of the light changes of eclipsing variables in the
Frequency Domain. The method was applied to 36 W UMa systems for which geometric and photometric elements have been derived
by the most powerful techniques. The derived values are very close to those predicted by the existing theory of radiative
transfer or convective equilibrium. 相似文献
2.
G. Djurašević P. Rovithis H. Rovithis-Livaniou E. Fragoulopoulou 《Astrophysics and Space Science》2005,296(1-4):311-314
BV light curves of the eclipsing binary UV Leo obtained at the Kryonerion Astronomical Station of the National Observatory of
Athens, Greece, are analyzed. The analysis is based on a Roche configuration with two spots on the secondary surface. The
elements of the two components of the system are calculated and the spot characteristics are given. 相似文献
3.
Qing-Yao Liu Yu-Lan Yang National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming 《中国天文和天体物理学报》2006,6(3):331-337
The variation in the orbital period of the W UMa type contact binary V502 Oph is analyzed. The orbital period exhibits a wavelike variation with a periodicity of 23.0 years and an amplitude of △P = 1.24×10~(-6) days superimposed on secular decrease of dP/dt = 1.68×10-7 day per year. The long-term decrease may be accompanied by the contraction of the secondary at a rate of 83 m per year and a mass transfer rate from the primary to the secondary of 4.28×10~8 M per year. The short-term oscillation may be explained by the presence of a third component. Orbital elements of the third body and its possible mass are presented. 相似文献
4.
5.
本文从动力学定律出发,推导了一个线性的、具有下垫面温度耦合的大气环流的统计—动力模式,并用该模式对500hPa高度场及1000hPa温度场作1~30天的平均预报试验。模式的预报结果大大优于惯性预报,但耦合与不耦合的结果差别不大。 相似文献
6.
Long Waves Associated with Bichromatic Waves 总被引:1,自引:0,他引:1
DONG Guohai 《中国海洋工程》2001,(2):281-289
A numerical model of low frequency waves is presented. The model is based on that of Roelvink (1993), but the nu-merical techniques used in the solution are based on the so-called Weighted-Average Flux (WAF) method with Time-Operator-Splitting (TOS) used for the treatment of the source terms. This method allows a small number of computational points to be used, and is particularly efficient in modeling wave setup. The short wave (or primary wave) energy equation is solved with a traditional Lax-Wendroff technique. A nonlinear wave theory is introduced. The model described in this paper is found to be satisfactory in modeling low frequency waves associated with incident bichromalic waves. 相似文献
7.
8.
The application of very large floating structure (VLFS) to the utilization of ocean space and exploitation of ocean resources has become one of the issues of great interest in international ocean engineering field. Owing to the advantage of simplicity in structure and low cost of construction and maintenance, box-type VLFS can be used in the calm water area near the coast as the structure configuration of floating airport. In this paper, a 3D linear hydroelastic theory is used to study the dynamic response of box-type VLFS in sinusoidal regular waves. A beam model and a 3D FEM model are respectively employed to describe the dynamic characteristics of the box-type structure in vacuum. A hydrodynamic model (3D potential theory of flexible body) is applied to investigate the effect of different dry models on the hydroelastic response of box-type structure. Based on the calculation of hydroelastic response in regular waves, the rigid body motion displacement, flexible deflection, and the short term and long 相似文献
9.
Martin Groenewegen 《Astrophysics and Space Science》1995,224(1-2):321-324
The relation between mass loss rate and pulsation period in carbon Miras is discussed. The dust mass loss rate is very low (about 2 × 10–10 M/yr) up to aboutP = 380 days, where there is a sudden increase. ForP > 400 days there is a linear relation between logM andP. The change in the mass loss rate near 380 days may be related to radiation pressure on dust becoming effective in driving the outflow. 相似文献
10.
GIS工作流系统的长事务处理研究 总被引:3,自引:0,他引:3
分析了Sagas事务模型及空间数据版本树技术,设计了一种灵活的长事务补偿控制方案,为集成GIS,MIS及OA的工作流系统提供了有力的事务处理技术支持。 相似文献